Method of bleaching cotton fabrics with tetrachloromalonamides



Un ted S a s METHOD OF BLEACHING COTTON FABRICS WITH TETRACHLOROMALONAMIDES Michael Kokorudz, Southgate, Mich., assignor to Wyan dotte Chemicals Corporation, Wyandotte, Mich., a corporation of Michigan 3 Claims. c1. 8- 108) This invention relates to new active chlorine bleach compounds. In a further aspect, this invention relates to new organicsolid bleach compounds, one of which is, additionally, an outstandingly effective germicide.

- This application is a division'of application Serial No. 744,013, filed June 23, 1958. p I

Much effort has been expended in recentyears towards the development of solid bleach compounds which are eflicient bleaching agents while being safe under the conditions of use in the home and industry both with respect" to the user and to the fabrics undergoing bleaching. Thus, a search is continuing for suitable solid bleach compounds which can replace the traditional hypochlorite solution bleaches, such as the solution bleaches based on sodium hypochlorite or calcium hypochlorite, which have been inconvenient to handle because they are available only in solution form and which have been undesirable under use conditions because of the tendency to weaken fabric strength and to harm the hands of a personusing the bleach. Some commercial acceptance has been found for such organic active chlorine bleach compounds as dichlorocyanuric acid, trichloroisocyanuric acid and 1,3 dichloro 5,5 dimethylhydantoin. Certain disadvantages have been found with all such known organic active chlorine solid bleach compounds and so the search continues for new and effective organic solid bleach compounds.

' An object of this invention, therefore, is to provide a new and efiective active chlorine solid bleach compound.

A further object of this invention is to provide a methodof'bleaching cotton fabrics with a new active chlorine organic solid bleach compound.

Mea

A still further object is to provide a new method for preparing an organic solid bleach compound. These objects and others have been accomplished in this invention by the discovery of new and effective active chlorine, organic solid bleach compounds corresponding to the formula N,N'-d,a-tetrachloromalonamide. The new bleach compounds are readily prepared in high yields as white solids which require little or no purification by the direct chlorination of the corresponding dialkylmalonamides. The new bleach compounds-have been found to. be at least The new active chlorine .as'efiective in bleaching cotton fabrics" as the known vention ,N,N' dimethyLN,N-a,a-tetrachloromalonamide organic solid bleach compounds, and under some conditions, superior to such compounds, and surprisingly, N,N'-dim'ethyl-N,N'-a,x-tetrachloromalonamide has been found to be a remarkably effective germicide, also.

The new bleach compounds of the invention can be formulated into desirable bleaching compositions by mixing in the substantially dry state with alkaline salts, 'such as sodium carbonate, sodium borate, sodium silicate, trisodium phosphate, tetrasodium pyrophosphate, sodium triphosphate or mixtures of these. In addition, wetting agents, synthetic detergents generally, soaps, fillers, abrasives and water softening agents of the inorganic or organic type may be incorporated in bleach compositions containing the new active chlorine organic bleach compounds of the invention in orderto impart special properties. e

The new bleach compounds of the invention are characterized by a high degree of stability when dry and may be stored for long periods of time and transported over considerable distances without substantial decomposition. When the newbleach compounds of the invention are dissolved in water, the ingredients of the mixture apparently react to yield hypochlorite chlorine which is resonsible for the efficient oxidizing, bleaching, disinfecting and sterilizing action.

The new bleach compounds of the invention are readily prepared as pure white solids in high yield and can be formed into tablets, sticks, cubes or agglomerates as well as in powdered form for use in bleaching operations.

The new bleach compounds of this invention are readily prepared by suspending N,N'-dimethylmalonamide or N,N'-dimethylmalonamide in an aqueous alkaline solution, cooling the resulting mixture to below about 10 C. and passing chlorine gas into the cooled mixture until the pH of the mixture is about 7-5 while maintaining the tempertaure at no more than about 30 C.

The aqueous alkaline solutioncan be a solution of sodium or potassium hydroxide or any alkaline-reacting inorganic salt, such as sodium or potassium carbonate or bicarbonate. However, ammonium salts should not be used because of the danger of forming nitrogen trichloride. The amount of alkaline compound to be used must be 4 moi-equivalents per mol of dialkylmalonamide in order to obtain the theoretical yield of the tetrachlorosubstituted product. Lesser amounts of alkaline compound will reduce the yield, and an excess is desirable.

The temperature of the mixture while thechlorine gas is passed in is desirably about (l -30 C. and preferably should not be substantially above about 10 C.

Chlorine gas is passed in over a period ,of time in the range of 2 to about 6 hours and until the pH of the reaction mixture is in the range of 7-5, desirably about 6.

When the addition of chlorine gasis completed the white solid product is easily separated fromthe reaction mixture by filtration and air-dried.

The new active chlorine organic bleach compounds of this invention and the method by which they can be prepared are illustrated in the'following examples which are intended to illustrate the invention without .unduly restricting it. a

' Example I N,N'-dimethylmalonamide was prepared by the reaction of diethylmalonate with methylamine as set forth in Beilstein, 4, 62; II, 56 5.- e e 2:; I",

bleach compound of thei-ing 2,980,488 Patented APP,

Chlorine gas was introduced to the aqueous alkaline solution of the dialkylmalonamide while cooling the mixture so that the temperature was in the range'of 46 C.

Chlorine gas was passed into the alkaline solution over.

a period of about 5 hours until the pH was 6.0. The white solid product which was produced was filtered and dried in air and weighed at room temperature. p I V A yield of 249 grams which Was 92.5% of the theoretical amount of N,N-dimethyl-N,N-d,a-tetrachloromalonamide was obtained. Analysis of the product showed the product to have a total chlorine content of 53.4% and an active chlorine content of 26.5% v

The active chlorine bleach compound preparedv vas tested for bleaching activity by dissolving a sulficient' quar tity of the product in a liter of water so that the concentration of the product was sufficient to provide 200' parts per million of available chlorine. Half of thissolution was cut fifty-fifty to provide a solution containing,

100 parts per million available chlorine. Deionized water was used to prepare all solutions.

The bleaching tests were carried out on six 4" x4," swatches of unbleached muslin which were prepared for the tests by washing them five minutes in a Terg-O- Tometer at 75 cycles per minute at 140 F. in'a 0.25 weight percent solution of a detergent composition consisting essentially of sodium alkylbenzenesulfonate, sodiurn carboxymethylcellulose and aninorganic alkaline salt such as is described in US. 2,566,501. The detergent composition employed had been prepared in one liter of demineralized water. Thereafter, the swatches were rinsed under a demineralized water tap. After'rinsing the washed swatches, the bleaching operation was carried out in the Terg-O-Tometer in the one liter of bleach solution prepared as described above for 15 minutes,at,75 cycles per minute at 140 F.

After bleaching, the swatches were removed from the bleach liquor, rinsed under the demineralized water tap and pressed dry.

The bleaching eflectiveness obtained in each test was.

measured by standard light reflectance techniques. The light reflectance of the bleached swatches was compared to the light reflectance of the swatches before bleaching using a blue filter in a Hunter Multi-Purpose,Reflectometer manufactured by Henry A. Gardner Laboratory, 1110., Washington, DC.

The test of the bleaching compoundprepared in this example at 200 parts per million provided a 64.3% re flectance in the bleached swatch in one sample and a 65.7% reflectance in anothercarried out under identical conditions. The test of the compound at 100 parts per million provided a reflectance of 61.3%.

The new active chlorine bleach compound prepared in this example was also evaluated for germicidal activity using the Stuart-Ortenzio modification of the Cantor- Shelanski Increment Loading Method. In the test, for germicidal activity, solutions of the new compound were prepared containing 50, 100 and 200 parts per. million of available chlorine in sterile deionized water.. Escherichia coli was the test organism used in the work, and this was carried by daily transfer to fresh flasks of FDA Broth so that the work was done with the same culture of test organism. In the test used, 12 incrementsof loading consisting of 0.05 ml. each of an actively growing culture ofthe test organism were added to 10 ml. of the test germicidal solution. The additions were spaced one and one half minutes apart. Exactly 60 seconds after the addition of an increment of loading, a standard 4 mm. loopful of the medication mixture was withdrawn from the medication tube and planted in a tube of sterile fluid thioglycollate medium, Difco. v The subculture tubes were incubated two days at 35 C. and then read. All of the work was done with the medication tubes submerged in a thermostatically controlled water bath operating at 20 C., :05 C.

The test for germicidal activity with the compound of the invention prepared in this example showed that the test organism was killed within the exposure time of 60 seconds at all increments of loading of 1 through 12 increments with the solutions having 100 and 200 parts per million of available chlorine. The killing of the test organism at all increments of loading at 1 through9 increments was found with the solution of the compound of the invention having 50 parts per million concentration of available chlorine. p p

The surprisingly effective nature of N,Ni-dirnethyl- N,N'-a,ct-tetrachloromalonamide as a germicide and the unpredictability in this. field are emphasized when one considers that N,N-diethyl-N,N'-u,a-tetrachloromalonamide, made and tested successfully as a bleachingfcornpound in Example 11 was found to be completely ineflec tive in the same test for germicidal activity. q

A second run for the preparation of N,N' -dimethy1- N,N'-a,a-tetrachloromalonamide was carried out following the procedure describedabove- To a 20% aqueous.

solution of sodium carbonate (prepared by dissolving 122 grams of Na CO in 610 mlrof H 0) and cooled t0;

product was filtered and dried in a desiccator. The yield was 119 grams of product having a melting point of 130 132 C. which was 90% of theoretical yield.

Analysis of the product showed it to contain 26.9% active chlorine and 55.5% total chlorine.

The product was tested for bleaching effectiveness according to the procedure described above and solutions of the product containing 100 parts per million of available chlorine bleached the swatches to the extent of 65.4% reflectance at pH 4, 67.8% reflectance at pH 7 and 63.5% reflectance at pH 10. These results are generally equal to or superior to the bleaching effectiveness of 1,3-

bleached swatches under comparable conditions having 66.267.2% reflectance at pH 4, 64.2-65.9% reflectance at pH 7 and 61.5% reflectance at pH 10.

Example ll N, N-diethylmalonamide was prepared by the reaction of dlethylmalonate with ethylamine by themethod cited at the beginning of Example I.

The N,N' diethyl N,N'-a,a-tetrachloromalonamide compound of the invention was prepared by suspending 158 grams (1 mol) of N,N-diethylmalona1nide in a solution of 222 grams (2.1 mols) of Na CO in 1550 ml. of water which was cooled to 4 C. The PH (1)? (the alkaline solution of the dialkylmalonamide was Chlorine gas was introduced to the aqueous alkaline solution of the dialkylmalonamide while maintaining the temperature of the reaction mixture at 6 C. to 4 C. over a period of about hours and until the PH was 6.0;

The white solid product which resulted was" filtered and dried in air for 24 hours.

A yield of 324 grams which corresponded to of the theoretical amount of product was obtained which had a melting point of -87 C., an active chlorine con tent of 23.8% and a total chlorine content oi": 45.7%.

dimethyl-N,N'-a,vr-tetrachloromalonamide is a surpris- 10 ingly eflective germicidal agent, also. The new compounds are, therefore, the basis for new methods and compositions for bleaching cotton fabrics employing these compounds as the active agent. Also, the new method by which organic solid bleach compounds have been prepared is considered as an embodiment of this invention. Furthermore, N,N dimethyl- N,N' cam-tetrachloromalonamide is an active germicidal agent and can be employed in aqueous germicidal rinse compositions containing a suflicient amount of this compound to provide at least about 50 parts per million of available chlorine.

I claim;

1. A method for bleaching cotton fabrics, which comprises, contacting said fabrics with an aqueous solution of a compound corresponding to the formula C10 01001 I II I ll I wherein R is a member selected from the group consisting of methyl and ethyl radicals.

2. A method according to claim 1 wherein said compound is the compound represented by the formula O10 O10 Cl 3. A method according to claim 1 wherein said corn pound is the compound represented by the formula C10 C10 Cl No references cited.

, UNiTE'D STATES PATENT OFFICE CERTIFICATE @F CORRECTION Patent No. 2,980,488 April 18, 1961 Michael Kokorudz It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent. should read as "corrected below.

Column 2 line 32 for "dimethylmalonamide" read diethy1malonamide line 37, for "tempertaure" read temperature column 3, line 8 for "additional" read addition column 4, line 63, for "PH" read pH Signed and sealed this 10th day of October 1961.,

' (SEAL) Attest:

ERNEST W. SWIDER DAVID L. LADD I Commissioner of Patents Attesting Officer USCOM M-DC UNlTE'D STATES PATENT OFFICE CERTIFICATE 0F CORRECTION Patent No. 2380,4853 April 18, 1961 Michael Kokorudz It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent. should read as "corrected below.

'dimethylmalonamide" read Column 2, line 32, for

for "tempertaure" read diethylma'lonamide line 37 temperature column 3, line 8 for "additional" read addition column 4, line 63, for "Pl-l" read pH Signed and sealed this 10th day of October 1961.

' (SEAL) Attest: ERNEST W. SWIDER DAVID L. LADD Commissioner of Patents Attesting Officer USCOMM-DC 

1. A METHOD FOR BLEACHING COTTON FABRICS, WHICH COMPRISES, CONTACTING SAID FABRICS WITH AN AQUEOUS SOLUTION OF A COMPOUND CORRESPONDING TO THE FORMULA 